| 摘要 |
PURPOSE:To make cutting-process of the scroll member in the caption easy and of lower cost, by previously forming a part which is lower than other parts in a place apart from an extended scrolling space in a scroll element. CONSTITUTION:A fixed scroll member 15 is made of cast material on which machine-finishing is applied through cutting process. A scroll element 152 is formed to shape a scroll line around an axis. An end plate 151 is a circular disc having a diameter by which it is closely fitted to the inner wall of a housing 10 as an integral part of said scroll element 152 at one end thereof. Here, a lower part 155, which is formed on the surface of said end plate 151 continuously from the outmost end of the scroll of said scroll element 152, extends itself from the outer rim of said end plate 151 slightly inward with respect to an extended curved line of the inner wall of said scroll element 152, with its height smaller than the height of the finished surface of the other part of said end plate 151. Due to the above construction, said end plate 151 can be machine-finished without leaving unfinished part by moving an end mill only within a required range. |
